Air diffuser



E. H. PERSON 3,260,188

AIR DIFFUSER 3 Sheets-Sheet l July 12, 1966 Filed June 5, 1964 July 12, 1966 E. H. PERSON 3,260,188

AIR DIFFUSER Filed June 5, 1964 3 Sheets-Sheet 2 E. H` PERSON July 12, 1966 AIR DIFFUSER 5 Sheets-Sheet 3 Filed June 5, 1964 @Mlm @Mlm W United States Patent O 3,260,188 AIR DIFFUSER Ernest Hjalmar Person, New Britain, Conn., assignor to Allied Thermal Corporation, New Britain, Conn., a

corporation of Connecticut Filed June 5, 1964, Ser. No. 372,776 9 Claims. (Cl. 98-40) The present invention relates to air diffusers and more particularly to air diffusers of the Aslot type in Which the Iair outlet is in the form ot' an elongated slot.

Many forms of air diffusingdevices have been used to supply air from a heating or cooling sys-tem to a room. Slot-type .diffusers in which the air emitting `opening is an elon-gated slot have been found particularly .desirable for certain types of installations, especially where the air outlet is to be flush with a ceiling surface or in association with a conventional troffer light fixture for diffus-ing air along the lateral edge of .the fixture.

The principal object of the present invention has .been the provision of a novel and improved slot-type air diffuser.

Another object of the invention has been the provision of a novel and improved slot-type air diffuser adapted for mounting with the air outlet flush or substantially flush with a ceiling or other Wall surface and which permits convenient adjustment .of the direction of air flow.

A further object of the invention has been the provision of such a diffuser which is readily adjustable with respect ,to the pattern of the emitted air and which permits simultaneous achievement of more than one pattern.

Another object of the invention has been the provision yof such a diffuser in which the air pattern direction can her controlled within a range of approximately 180 by simple adjustments. i

A further object of the invention has been the provision of such a diffuser Which is especially adapted for use with a treffer lighting fixture.

IOther and further objects, features and advantages of the invention will appear more fully from the following description taken in connection :with the appended drawings, in which: v

`FIG. 1 is a top plan view of one form of slot-type air diffuser embodying the .present invention;

FIG. 2 is a front elevational view of the diffuser of FIG. 3 is a perspective view, taken from the rear, of the diffuser of FIG. 1;

FIG. 4 is a right-side elevational View of the diffuser of FIG. l;

FIG. 5 isa cross-sectional view taken along the line FIG. 6 is a fragmentary sectional view corresponding to a portion of FIG. 5 and showing one of the air pattern directing elements in a different position from that shown in FIG. 5;

FIG. 7 is a fragmentary sectional view corresponding .to a portion of FIG. 5 and showing one of the air pattern .directing elements in still another different position;

|FIG. 8 is a fragmentary sectional view taken along the v.une s s of PIG. 2;

Patented July 12, 1966 ICC preferably made of sheet metal, and comprising a fron-t wall 20, a rear wall 21, a top wall 22, a bottom wall 23, and a pair of end walls 24 and 215. The .front and rear walls 20 and 21 may be considered as relatively long side walls joined `by relatively short end walls 24 and 215. The walls 20-23 may be formed from a single strip of sheet metal, as shown, or from two or more strips suitably joined. The Walls 20-23 are formed by suitably bending the sheet metal, the free ends being locked together by lmeans `of an inturned iiange 26 on top wall 22 bent over a rearwardly projecting flange 27 of rear wall 21. The walls 204.3 may be of any desired length, but typically 'will be from 2 to 4 feet in length.

The end walls 24 and 25 are -recessed slightly int-o the housing and are held in place in the housing by means of projecting tabs 2S which extend through corresponding holes in the housing and which are bent over, as best shown in FIG. 2 and 3.

An elongated, axially centered, rectangular slot 29 is `provided in bottom wall 23. The slot 2x9 preferably extends continuously frorn end wall 24 to end Wall 25. The slot 29 serves to discharge air from the diffuser and hence the diffuser is preferably mounted so that slot 29 is substantially finish wi-th the ceiling surface of the room being ventilated. Of course, there may be a minor spacing between slot 29 and the ceiling, eig., the thickness of the side flange of a troffer housing. Typically, .the slot 29 might have a width of '/16, while the opposing portions of Ibottom wall 23 on opposite sides of slot 29 might each have a width of 1A. The foregoing and other dimensions .set forth herein are given only by way of example and should not be taken as limiting the invention.

Rear wall 21 is divided into an upper portion 30 and a lower portion 31 by a horizontal shoulder 32, affording an upper chamber 33 and a lower chamber 34. Typically, the upper chamber 33 might have a Width (front to back) of 115716, while the lower chamber 34 might have a width of 15/16". Typically, the overall height of the housing might be 7 7A; while the height of the chamber 34 might be 4%.

A :spacer 35, best shown in FIG. l0, is` mounted between front wall 20 and rear wall 21 at the axial middle of the housing and is held in place by projecting tabs 36 which extend through holes in the front and rear Walls and .are bent over. The spacer 35 is U-shaped with the open end of the U facing downward. Preferably the spacer 35 rests on the upper surface of bottom wall 23.

Flat spacers 37 .and 38 are provided between Walls 20 and 21 intermediate spacer 35 and end walls 24 and 25, respectively. Spacers 37 and 38 are located above bottom wall 23 but below .the level of shoulder 32. Spacers 37 and 38 are held in .place by projecting tabs 39, which extend through holes in the front and rear walls and are bent over.

Front wall 21 is provided with a centrally located oval opening 40 in which is mounted an oval air inlet tube or duct 41. The duct 41 has -a radially extending flange 42 "which may be welded or otherwise affixed to front wall 21.

The duct 41v is intended to communicate with a supply of conditioned air, eLg., a main or branch duct, by lany suitable coupling (not shown). An adjustable damper 43 is pivotally mounted in duct 41 and may be shifted to any position between the open position shown in full lines in FIG. 5 and the closed position shown in dotted lines in FIG. 5. 'A hook formation v44 at one end of damper 43 facilitates adjustment of the damper by means of a tool inserted through slot' 29. The damper 43 is retained tightly in duct 41 so` that the damper will stay in whatever position it is placed.

End Walls 24 and 25 are each provided with a centrally located round hole adjacent the bottom edge thereof, these holes being ydesignated 45 and 46, respectively. Round generally by the arrows 57 and 58.

holes 47 and 48 are provided in therrespective legs of spacer 35, the holes 47 .and 48 being axially aligned with holes 45 and 46.

A pair of cylindrical deiiectors 49 and 50 are mounted between end wall 24 and the facing leg of bracket 35, and between end wall 25 and the facing leg of bracket 35, respectively. The deectors 49 and 50 are preferably hollow metal tubes. Deector 49 has a pair of axially aligned lugs 51 and 52 proje-cting in an axial direction from opposite ends thereof, while deflector 50 has a similar pair of axially 4aligned lugs 53l and 54 projecting in an axial direction from opposite ends thereof. Lugs 51 and 52 it into holes 45 land 47, respectively, while lugs 53 :and 54 lit into holes 46 and 48, respectively. The lugs 51-54 acting in the respective corresponding holes serve to support the respective deectors 49 and 50.

The length of the tubes 49 and 5t) is slightly greater than the spacing between end walls 24 and 25 and the respective facing legs of spacer 35 when the latter lare in an unstressed condition. Accordingly, the legs of spacer 35 must be forced toward each other to insert the deiectors 49 and 51), and will remain slightly stressed with the deflectors in position. In other words, spacer 35 acts as a spring urging the ends of deflectors 49 and 50 into contact with the end walls 24 and 25, respectively, so that the deflectors 49 and 50 will stay in whatever rotative position they are placed.

The lugs 51-54 are smaller in width than the corresponding holes 45-43 so that the deflectors may be rotated manually about axes joining the lugs 51 and 52 and 53 and 54, respectively. In FIG. 5, the deector 50 is shown in contact with rear wall Z1. In FIG. 6, the deflector 5) is shown in contact with front wall 20. FIGS. 5 and 6 thus represent opposite extreme positions for the deflector 50. The deflector 50 may be placed in any intermediate position, e.g., the one shown in FIG. 7, which represents an intermediate position midway between the FIG. 5 and FIG. 6 positions. The deilector 49 is independently .positionable in positions corresponding to those described for deflector 50. It is not necessary that the deflectors 49 and 50 be placed in the same or similar positions, since each may be independently adjusted to obtain a desired air pattern, as will be described below.

Deflectors 49 and 50 have diameters equal to one-half the distance between front wall and lower portion 31 of rear wall 21, so that the FIG. 5 and FIG. 6 extreme positions correspond substantially exactly. It is desirable that in the extreme deflector positions the deflectors contact both the rear or front wall, as the case may be, and the bottom wall 23 so that there will be two lines of contact between the deflector and the housing to minimize air leakage between the deflector and the adjacent housing wall in the extreme deflector positions. This contact is particularly desirable where two -or more independently adjustable deectors are provided, since, if the deflectors are adjusted differently, shear effects in the air stream must be overcome and these will be .aggravated by air leakage behind the deectors. However, where only a single deflector is provided, or where the deectors are similarly adjusted, satisfactory operation will be achieved without contact of the deilector or deilectors with the rear or front wall and the bottom wall of the housing. In such case it is suicient if the deflector or deectors lie adjacent the vrear or front wall, as the case may be, so as to prevent -ferring to FIG. 7, with the deilector 50 in :the middle position shown, the air ilow pattern is downward, as shown In any intermediate deector position between FIGS. 5 and 7, the air 110W will be intermediate the directions shown by arrows 55 and 57-58. In any intermediate deector position between FIGS. 6 and 7, the air ow will be intermediate the directions shown by .arrows 56 and 57-58. The air patterns obtainable with deflector 49 are adjustable in the same manner as described for deflector 50. The deflectors may be moved from position to position by insertion of an appropriate tool through slot 29 and pivoting of the deilector as desired.

An important advantage secured by the construction of the invention is that, irrespective of the air pattern selected, the effective area or discharge area of the diffuser will be substantially constant. That the air discharge areas for horizontal right and horizontal left patterns are identical will be evident from a comparison of FIGS. 5 and 6. The air discharge areas for the downblow position of FIG. 7 or for intermediate positions is not readily determinable except by a measurement of the amount of static pressure required to force a given volume of air through the diffuser. However, such static pressure measurements show that the air discharge areas remain substantially unchanged between the horizontal patterns of FIGS. 5 and 6 and the downblow pattern of FIG. 7.

The results of actual static pressure measurements are shown below. In these measurements the diffuser had the dimensions and shape described above except that the overall diffuser height was 6, while the height of chamber 34 was 21/2. The height of inlet duct 4I was 3". The inlet static pressure (in inches of water) was measured in duct 41, the drop in pressure (AP) was measured across an orifice. Air volume was in cubic feet per rmnute.

Inlet S.P. AP Direction .11 .079 Down (Fig. 7).

. 108 079 One Way (Fig. 6).

.122 079 One Way (Fig. 5).

. 112 079 Two Way (Figs. 5-6).

.178 Down (Fig. 7).

.175 125 One Way (Fig. 6).

.193 125 One Way (Fig. 5).

. 182 125 Two Way (Figs. 5-6).

. 25 .182 Down (Fig. 7).

. 246 182 One Way (Fig. 6).

. 275 .182 One Way (Fig. 5).

. 257 182 Two Way (Figs. 5-6).

When it is considered that the volume varies essentially as the square root of the pressure change so that a 10% change in static pressure would correspond approximately to a 3% (ill/2%) change in volume, the effective area of the slot diffuser for different deflector positions shown in the table is remarkably constant. For the purposes of measurement, the two deflectors were identically adjusted except for the two-way condition. In that condition one deector was adjusted as in FIG. 5 and the other as in FIG. 6.

If desired, the lower chamber 34 may be connected directly to an air duct or other source of air, thus eliminating the chamber 33 and associated parts.

While the invention has been described in connection with a specific embodiment thereof and in a specific use, various modifications thereof will occur to those skilled in the art without departing from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

1. An air diffuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls and a bottom wall, said bottom wall having an elongated slot extending substantially from one end wall to the other end wall and being located substantially midway between said side walls, the portions of said bottom wall on each side of said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said bottom wall, and means selectively to alter the pattern of air discharged through said slot cornprising an elongated cylindrical deflector element having a diameter approximately equal to one-half the width of said bottom wall, means to mount said deector element in said housing generally above said slot and shiftable between a first position in which said deflector element is in substantially sealing contact with one of said side walls and the adjacent lip of said bottom wall and a second position in which said deflector element is in substantially sealing contact with the other of said side walls and the adjacent lip of said bottom wall, said mounting means being arranged to permit manual shifting of said deflector element between said first and second positions and to retain said defiector element in any of said first position, said second position and any intermediate position.

2. An air diffuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said `side walls and .a bottom wall, said bottom wall having an elongated slot located between said side walls, at least the portion of said bottom wall on one side of said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said bottom wall, and means selectively to alter the pattern of air discharged through said slot comprising an elongated cylindrical deflector element, means to mount said deflector element in said housing generally above said slot and shiftable between a first position in which said dellector element lies adjacent one of said side walls and a second position in which said deflector element lies adjacent the other of said side walls, said mounting means being arranged to permit manual shifting of said deector element between said first and second positions and to retain said deflector element in either of said first position and said second position.

3. An air diffuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls, a top wall and a bottom wall, said bottom wall having an elongated rectangular slot extending substantially from one end wall to the other end wall and being located substantially midway between said side walls, the portions of said bottom wall on each side of said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said vbottom Wall, and means selectively to alter the pattern of air discharged through said slot comprising an elongated cylindrical deflector element, means to mount said deflector element in said housing generally above said slot and shiftable between a first position in which said deflector element is in substantially sealing contact with one of said side walls and a second position in which said detlector element is in substantially sealing contact with the other of said side walls, said mounting means being arranged to permit manual shifting of said deflector element between said first and second positions and to retain said defiector element in any of said first position, said second position and any intermediate position.

4. An air diffuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls, a top wall and a bottom wall, said bottom wall having an elongated rectangular slot extending substantially from one end wall to the other end wall and being located substantially mid- Way between said side walls, the portions of said bottom wall on each side of said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said bottom wall, and means selectively to alter the pattern of air discharged through said slot comprising a pair of axially aligned elongated cylindrical detlector elements each having a diameter approximately equal to one-half the width of said bottom wall, means to mount said deflector elements in said housing generally above said slot and independently shiftable between a lirst position in which each said dellector element contacts one of said side walis and the adjacent lip of said bottom wall and a second position in which each said defiector element contacts the other of said side walls and the adjacent lip of said bottom wall, said mounting means being arranged to permit independent manual shifting of said deflector elements between said first and second positions and to retain said defiector elements selectively in any of said rst position, said second position any intermediate position.

5. An air diffuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls, a top wall and a bottom wall, said bottom wall having an elongated rectangular slot extending substantially from one end wall to the other end wall and being located between said side walls, the portions of said bottom wall on each side of said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said bottom wall, a generally U-shaped spacer joining said side walls at a point intermediate said end walls, said spacer having the open end of the U facing downwardly and having the legs of the U substantially parallel to said end walls, said end walls and said legs of said spacer each having a hole spaced above the plane of said bottom wall, the centers of said holes being located in a line parallel to and aligned with the axial center line of said slot, and a pair of elongated cylindrical deflector elements each having an axially aligned axially projecting lug extending from each end of the periphery thereof, the lugs of one of said deflector elements extending into and being rotatably retained in respective ones of said holes in one of said end walls and the facing one of said legs and the lugs of the other one of said deflector elements extending into and being 4rotatably retained in respective ones of said holes in the other one of said end walls and the other one of said legs, said deflector elements being independently shiftable between a lirst position in which said deliector elements contact one of said side Walls anda second position in which said deflectot` ,elements contact the other of said side walls, said spacer exerting an axial force on said deflector elements whereby t said deector elements are retained independently and sclectively in any of said first position, said second position and any position intermediate said first and second positions.

6; An air diffuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls, a top wall and a bottom wall, ysaid bottom wall having an elongated rectangular slot extending substantially from one end wall to the other `end wall and being located substantially midway between said side walls, the portions of said bottom wall on each side of said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air Will be discharged from said housing through said slot in said bottom wall, a generally U-shaped spacer joining said side walls substantially midway between said end walls, said spacer having the open end of the U facing downwardly and having the legs of the U substantially parallel to said end walls, said end walls and said legs of said spacer each having a round hole spaced above the plane of said bottom wall, the centers of said holes being located in a line parallel to and aligned with the axial center line of said slot, and a pair of elongated cylindrical deflector elements each having an axially aligned axially projecting lug extending from each end of the periphery thereof, the lugs of one of said deiiector elements extending into and being rotatably retained in respective ones of said holes in one of said end walls and the facing one of said legs and the lugs of the other one of said deflector elements extending into and being rotatably retained in respective ones of said holes in the other one of said end walls and the other one of said legs, said deliector elements being independently shiftable between a first position in which said deector elements con-tact one of said side walls and the adjacent lip of said bottom wall and a second position in which said deiiector elements contact the other of said side walls and the adjacent lip of said bottom wall, said spacer exerting an `axial force on said deector elements whereby said deiiector elements are retained independently and selectively in any of said iirst position, said second position and any position intermediate said rst and second positions.

7. An air diiuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls and a bottom wall, said bottom wall having an elongated rectangular slot extending substantially from one end wall to the other end wall and being located between said side walls, at least the portion of said bottom wall on one side of said slot forming an lelongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said bottom wall, and means selectively to alter the pattern of air discharged through said slot comprising an elongated cylindrical deflector element, means to mount said deector element in said housing generally above said slot and shiftable between a first position in which said deflector element lies adjacent and in substantially sealing relationship with one of said side walls and a second position in which said detiector element lies adjacent and in substantially sealing relationship with the other of said side walls, said mounting means being arranged to permit manual shifting of said dellector element between said iirst and second positions and to retain said detlector element in either of said first position and said second position.

8. An air dituser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls and a bottom wall, said bottom wall having an elongated rectangular slot extending substantially from one end wall to the other end wall and being located substantially midway between said side walls, the portions of said bottom Wall on each side of said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said bottom wall, and means selectively to alter the pattern of air discharged through said slot between directions substantially parallel to the plane of said bottom wall and substantially perpendicular to the plane of said bottom wall comprising a pair of axially aligned elongated cylindrical deector elements each having a diameter approximately equal to one-half the width of said bottom wall, means to mount said deflector elements in said housing generally above said slot and independently shiftable between a iirst position in which each said deiiector element contacts one of said side walls and the adjacent lip of said bottom wall and a second position in which each said deector element contacts the other of said side walls and the adjacent lip of said bottom wall, said mounting means being arranged to permit independent manual shifting of said deect'or elements between said first and second positions and to retain said detlector element selectively in any of said lirst position, said second position and any intermediate position.

9. An air diffuser, comprising a housing having a pair of relatively long side walls, a pair of relatively short end walls connecting said side walls and a bottom wall, said bottom wall having an elongated rectangular slot extending substantially from one end wall to the other end wall and being located between said side walls, the portions of said bottom wall on each side lof said slot forming an elongated lip, means in said housing for admitting conditioned air under pressure into said housing whereby air will be discharged from said housing through said slot in said bottom wall, a generally U-shaped spacer joining -said side walls at a point intermediate said end walls, said spacer having the legs of the U substantially parallel to said end walls, said end walls and said legs of said spacer each having a hole spaced above the plane of said bottom wall, the centers of said holes being located in a line parallel to and aligned with the axial center line of said slot, and a pair of elongated cylindrical deilector elements each having an axially aligned axially projecting lug extending from each end of the periphery thereof, the lugs of one of said detlector elements extending into and being rotatably retained in respective ones of said holes in one of said end walls and the facing one of said legs and the lugs of the other one of said deector elements extending into and being rotatably retained in respective ones of said holes in lthe other one 4of said end walls and the other one of said legs, said deiiector elements being independently shiftable between a iirst position in which said deflector elements lie adjacent and in substantially air sealing relationship with one of said side walls and the adjacent lip of said bottom wall and a second position in which said deflector elements lie adjacent and in substantially air sealing relationship with the other of said side walls and the adjacent lip of said bottom wall, said spacer exerting an axial force on said deflector elements whereby said deiiector elements are retained independently and selectively in any of said iirst position, said second position and any position intermediate said rst and second positions.

References Cited by the Examiner UNITED STATES PATENTS 3,099,949 8/1963 Davidson 98-40 WILLIAM F. ODEA, Primary Examiner.

ROBERT A. OLEARY, Examiner.

I. F. OCONNOR, Assistant Examiner. 

1. AN AIR DIFFUSER, COMPRISING A HOUSING HAVING A PAIR OF RELATIVELY LONG SIDE WALLS, A PAIR OF RELATIVELY SHORT END WALLS CONNECTING SAID SIDE WALLS AND A BOTTOM WALL, SAID BOTTOM WALL HAVING A ELONGATED SLOT EXTENDING SUBSTANTAILLY FROM ONE END WALL TO THE OTHER END WALL AND BEING LOCATED SUBSTANTIALLY MIDWAY BETWEEN SAID SIDE WALLS, THE PORTIONS OF SAID BOTTOM WALL ON EACH SIDE OF SAID SLOT FORMING AN ELONGATED LIP, MEANS IN SAID HOUSING FOR ADMITTING CONDITIONED AIR UNDER PRESSURE INTO SAID HOUSING WHEREBY AIR WILL BE DISCHARGED FORM SAID HOUSING THROUGH SAID SLOT IN SAID BOTTOM WALL, AND MEANS SELECTIVELY TO ALTER THE PATTERN OF AIR DISCHARGED THROUGH SAID SLOT COMPRISING AN ELONGATED CYLINDRICAL DEFLECTOR ELEMENT HAVING A DIAMETER APPROXIMATELY EQUAL TO ONE-HALF THE WIDTH OF SAID BOTTOM WALL, MEANS TO MOUNT SAID DEFLECTOR ELEMENT IN SAID HOUSING GENERALLY ABOVE SAID SLOT AND SHIFTABLE 